The Preparation And Research About Optical Properties Of Silver Nanoparticles

Owing to special effects, such as the quantum size effect, nano-materials possess valuable physical and chemical properties that bulk material does not have. Metal nanostructure has been extensive studied for its unique properties in optical, electrical, magnetic, catalysis, biochemistry field. Silver nanoparticles have shown distinct manifestation in biomedicine, catalysis, optics, thus they have gain importance in nanotechnology.With the development of nanotechnology the rang of application about silver nanoparticles is more and more widely in recent years. For example, as a new antibacterial, it is non-tolerance, highly safety and can be used to be antibiosis fabric such as surgical gauze. The property of nanoparticles is mostly influenced by their size and morphology,thus the controllable preparation becomes a hot topic in current studies.Silver nanoparticles have many preparation methods,but we usually use chemical reduction,which is easy to operate. Howwever, dispersing agent or stabilizer should be added in the process,which can cause environmental pollution,do harm to human body and gain the cost of production, we find it is a new trend to use non-toxic regents for prepartion.In this paper, the controllable preparation and optical properties about silver nanoparticles were stuied, which were based on chemical reduction method, green method and characterization. The main research works and conclusions are as following:1. Sodium laurate or oleic acid as protective agent, hydrazine hydrate as reducing agent and silver nitrate as precursor, we chose chemical reduction method to react several hours at room temperature, thus silver nanoparticles with small size were successfully prepared. Then, we used UV-Vis absorption spectra,TEM and XRD to study the chemistry properties of silver nanoparticles.2. In this period, we prefer green method, that is no chemical reagent as reducing agent but only mulberry leaf extract to achieve the green synthesis of silver nanoparticles. After reacting 2 hours at room temperature, we got spheral silver nanoparticles whose size rang from 5nm to 15 nm. After further research, we found that amount of extract, silver nitrate concentrations, reaction time and reaction temperature would have an effect on the size of silver nanoparticles. For example, the more amount of extract we added, the more silver nanoparticles and lager size we got.